6. Mechanical properties of molybdenum and its alloys

6.1 Fragility near room temperature

The transition temperature of molybdenum is close to room temperature, with transgranular fracture in the ductile range, intergranular fracture in the brittle range, and mixed fracture in the transition zone. The low-temperature fracture facies of high-purity molybdenum shows a mixture of intergranular and cleavage fractures. The presence of these two fracture modes can be explained by the influence of grain boundary structure on grain strength. The joints of low-strength grains,...